That's a massive pain in the ass for those people, so what's Sony doing to compensate them for their enforced downtime? Sony Online Entertainment, which manages both PS3 MMOs, has this to say:

We apologize for any inconvenience players may have experienced as a result of the recent service interruption. As a global leader in online gaming, SOE is committed to delivering stable and entertaining games for players of all ages.

To thank players for their patience, we will be hosting special events this weekend across our game portfolio, including a Double Station Cash day on Saturday, April 30th.

We are also working on a "make good" plan for players of the PS3 versions of DC Universe Online and Free Realms. Details will be available soon on the individual game websites and forums.

So there's extra stuff on the table come Saturday, provided the PSN is actually up by then, and then there's a "make good" plan after that. It's a good start, but seeing as DC Universe is made up of people paying subscriptions you'd hope it's more like a "make awesome" plan.